The company says that it has since made "significant changes and improvements" to its services to ensure a similar outage doesn't happen again.
CEO John Legere takes to Twitter to update customers about network issues that hit an unspecified number of users on Friday.
Mobile operators have been preparing like mad to ensure that fans' selfies and video clips can be shared without a hitch.
Disruption to the carrier's network began around 6 p.m. PT but did not appear to affect all customers.
In a statement on Wednesday, the cellular carrier says that a software problem generated "abnormal congestion" on its network.
Customers affected by a widespread outage Tuesday share their grievances over both the technical issues and the way that the carrier handled the matter.
The cellular carrier acknowledges problems affecting both its voice and data networks.
Keeping track of where their data is stored, and whether it is truly protected is not a core competency for consumers. The T-Mobile outage proves it should be.
Outage that began Friday knocked out data service. Microsoft, whose Danger subsidiary powers the Sidekick service, says it has restored service for "critical applications."
On today's show, the iPhone is apparently storing your location data even when you've turned off the location tracking services. And law enforcement agencies and a cottage industry of iOS forensics companies have been taking advantage of these logs for years. Nevertheless, Steve Jobs appears to insist in an email to a customer that Apple is not tracking anyone. Really. Hunch shows you why you love both hummus and Macs, even if you don't love Apple. Plus, Sony is rebuilding its PlayStation Network security after its now five-day outage, and an innocent man is accused of child pornography because it's still just too damn hard to put a password on a WiFi network. --Molly